Polyether-modified silicones are obtained by performing a hydrosilylation reaction of a polyether having a terminal double bond with a hydrogen silicone using a noble metal catalyst. Since they have a polyoxyalkylene chain in the molecule, they have conventionally been widely used in various industrial fields as nonionic surfactants. It is also known in the art that different performance and properties are obtained depending on the type and modification rate of the polyether having a terminal double bond (Nonpatent document 1, Patent document 1).
[Nonpatent document 1] Siloxane Polymers, Stephen J. Clarson/J. Anthony Semlyen PTR PRENTICE HALL p. 334-348.
[Patent document 1] Japanese Laid-Open Patent Application No. 2000-327787.
In the manufacture of electrical and electronic equipment, surfactants are used for cleaning substrates etc., but if the surfactant remains in the substrate after use, it will have an adverse effect on the water resistance of ink, or the electrical properties of electronic parts. In order to remove it completely, it is therefore required that it be highly volatile. In the prior art, as an example of a typical silicone which could be used as a surfactant, a polyether-modified silicone was known having a surface tension at 25° C. of 25 mN/m or less in a 0.01 mass % aqueous solution, but since it was not sufficiently volatile, it remained in the substrate even after use.
After they have been used, surfactants are usually removed by heating, but in the case of electrical/electronic parts, the heat resistance of the parts must be taken into consideration which places an upper limit of 200° C. on the heating temperature. Until now, a polyether-modified silicone which volatilizes completely on heating to 200° C. or less was not known, and a polyether-modified silicone which had the dual properties of low surface tension and high volatility was not known.